Foot Pain

I’ve recently developed pain on the medial side of my left foot, around the mid foot area - sort of on the lateral side of the 1st metatarsal (i don’t think it’s high up enough to be talus/navicular, but i won’t rule it out)

i have pain when walking on that side of my foot, especially when i pronate (i have flat feet, but they have improved with foot strengthening exercises + orthotics), so i have tried to avoid walking on that side. it isn’t too bad to hop on, and i can still complete a full training session without realising any pain until i pull up. i have also just had 6 weeks of solid weekly competition, running 4 days a week - all on grass, which is my usual training load.

i have the state championships in 10 days time, with about 5 training sessions and a warm up meet before that - which is my biggest issue: do i ease off or try to run through it for the time being, and then take a couple of weeks off after state? would i lose anything by reducing the volume or even training in flats for a while?
i am very wary of the possibility of a navicular problem, but as it is only a recent development, i don’t want to rule out a sprain or even a stress reaction, which would be favourable at the moment.

what are your thoughts on the best possible course of action?